The Group of 20 summit begins in Pittsburgh with sporadic demonstrations and riots. An "unauthorized protest march" of about one thousand people was the starting point of several smaller demonstrations and the crowd responded to calls to disperse by "rolling trash bins, throwing rocks ... and smashing car windows", reports KDKA.
Riot police and the Pennsylvania National Guard dispersed the crowd with exotic crowd control measures such as O2 canisters, smoke bombs, "stun grenades that exploded with sharp flashes of light" and sound cannons that "emitted shrill beeps, causing demonstrators to cover their ears and back up." Authorities believe this is "the first time" the sonic weapon has been deployed against civilians in the United States.
The march turned chaotic at around the same time President Barack Obama and First Lady Michelle Obama arrived for meetings with leaders of the world’s major economies. At least 20 people are behinds bars and there are numerous minor injuries from the gas.
AFTER THE JUMP, watch a CNN report and videos uploaded by residents and protesters. SOUND WARNING: Turn volume down esp. if wearing headphones.